A practitioner's checklist for building one app that ships everywhere — String Catalogs, RTL layout, locale-aware formatters, translated assets, App Store metadata per market. Synthesized from 12 years of WWDC i18n sessions and Apple's HIG.
Five sequential phases. Get the string handling right first — without that, everything else is throwaway. Then layout that survives RTL and long languages, then locale-aware data formatting, then translated content and assets, and finally a process so localization stays current release-over-release.
Filter by impact, effort, market, or category. The market dimension helps prioritize: items tagged RTL or CJK can wait if you're not shipping there yet, but items tagged "all" affect every locale.
High-impact items that take less than a sprint. Most are config changes, formatter swaps, or single-file edits with disproportionate per-locale value.